Paleozoic and Precambrian rocks of Alaska and their role in its structural evolution

Acknowledging that there are large gaps in the knowledge of the geology of Alaska, the following threefold subdivision of Alaska into Paleozoic tectonic elements is proposed: Southern Alaska--the Alaska Range and farther south--is the northern end of the Paleozoic Cordilleran geosyncline that rims the eastern Pacific. Northern Alaska--the northeastern Brooks Range and the Arctic Coastal Plain--is underlain by a pre-Upper Devonian fold belt that may continue around the rim of the Canada Basin into the Franklinian geosyncline of the Canadian Arctic Islands. East-central Alaska, with a thinner, mainly carbonate rock section, seems to be a western extension of the Yukon shelf that separates the circum-Arctic geosynclinal trend from the Cordilleran geosyncline along the Pacific margin of southern Alaska.